1. Field of the Invention
The present invention relates to an image processing apparatus.
2. Description of Related Art
An electrophotographic printer is one of widely used image processing apparatuses and incorporates an image processing cartridge detachably mounted to the printer. The image processing cartridge includes a developer cartridge detachably mounted thereto. The image processing cartridge is a generally cylindrical container and holds toner therein. The toner is discharged through holes formed in the container which are adapted to open and close, and is supplied to the developing roller of the image processing cartridge. The developing roller then supplies the toner to the electrostatic latent image on the drum to develop the electrostatic latent image into a toner image.
The toner image is then transferred by the transfer roller to the print medium and subsequently fused on the print medium. The medium is then discharged out of the printer after fixing.
An electrophotographic printer designed to form color images incorporates image processing cartridges for the respective primary colors, and a developer cartridge for a specific color is detachably received in a cartridge-receiving section of the corresponding image processing cartridge. Deficiency of color printing systems involving separate developer cartridges for the constituent colors is in the inadvertent misplacement of the toner cartridges in the printer. Misplacement of the cartridges destroys printed color images.
Therefore, the developer cartridges are designed to be in different shape according to color, thereby preventing inadvertent misplacement of the developer cartridges.
Toners of the respective colors are not necessarily consumed at the same rate. It is quite often that a particular color is used more than any other colors. Colors used more than other colors depend on individual print data and therefore it is difficult to predict what color or colors should be manufactured more than other colors. Moreover, if the toner cartridges are different in shape according to colors, then it is difficult to determine how many unfilled cartridges should be manufactured for each color.
However, a conventional electrophotographic printer requires an image processing cartridge and a developer cartridge for each primary color. Manufacturing developer cartridges different in shape necessarily increases the number of kinds of cartridges and manufacturing costs.
In order to solve this drawback, electrophotographic printers has been proposed where the developer cartridge and the mounting construction therefor are of the same design and shape for all the toner colors, and one of ribs or the like formed at a specific area in the developer cartridge is cut off to selectively polarize the cartridge for a corresponding color. However, once the ribs are cut off, the individual cartridges become different shapes. If they are to be recycled, separately storing the developer cartridges according to shape is difficult and therefore adds cost to the recycled containers. This construction does not lend itself to recycling.